Posted on December 4, 2019
Antminer S3 ASIC Teardown #1
I obtained 2 Antminers this week from the local classifieds. They came without power supplies, and there was little to no information about how they function inside, so research was required into the chips themselves. I started tearing down one to see what made these machines tick. The most I could get from google is this little snippet: Model Antminer S3 from Bitmain mining SHA-256 algorithm with a maximum hashrate of 478Gh/s for a power consumption of 366W. That means its going through 478 Billion hashes every second, at 366W. That is about the same power usage as business class computer. They are also at 3 years old at this point so no longer profitable for bitcoin mining as of 2019
After a little more searching I found that the 2 boards in the system have the BM1382 chip. This a Bitmain produced Bitcoin mining ASIC chip with a core frequency of 250mhz. Take this number with a grain of salt, as this chip is built for mining bitcoins, and is extremely efficient at what it does. Each system board is market S3 Hash Board V1.3 and holds 16 of the ASIC chips. Each board also have direct power from a 2 6pin sockets, requiring 4 6 pin psu connectors to power the unit.
Each board connects to a controller board with a 20 pin cable. The controller board has a RJ45 jack for connecting the device to the internet, and obviously to configure it from a self hosted website, like a firewall or router. The controller board has a PIC32MX which is a mips based microcontroller that controls the ASICs and a ThinkPHY2 which is also a mips based processor, bu this one is featured for network. The ThinkPHY2 includes a MIPS 24K processor, five-port IEEE 802.3 Fast Ethernet Switch with MAC/PHY, one USB 2.0 MAC/PHY, and external memory interface for serial Flash, There is also a reset button on the board, and two unpopulated spots on the board, one for LAN and one for debug.(I might have to get a UART debug device and solder it to the circuit board.)